Mechanism for shoulder grinding



Oct. 10, 1961 A. o. c. STUCKEY 3,003,291

MECHANISM FOR SHOULDER GRINDING Filed March 23, 1959 2 Sheets-Sheet 1 INVENTOR. KILBERT 0. 6'. STUC'KEY,

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Oct. 10, 1961 A. 0. c. STUCKEY 3,003,291

MECHANISM FOR SHOULDER GRINDING Filed March 25, 1959 2 Sheets-Sheet 2 Fig.2

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United States Patent C 3,003,291 IVIECHANISM FOR SHOULDER GRINDING Albert D. C. Stnckey, Cincinnati, Ohio, assignor to The Cincinnati Nlilling Machine Co., Cincinnati, Ohio, a corporation of Ohio Mar. 23, 1959, Ser. No. 801,243 1 Claim. (Cl. 5134) The present invention relates to an improved mechanism for a center-type grinding machine particularly suitable for successive reciprocating plunge cut grinding and shoulder grinding.

In plunge cut grinding on a center-type grinding machine, where a surface parallel to the axis of the wheel and no longer than the width of the wheel is ground by the peripheral surface of the wheel as the wheel is fed into the work, it is often desirable to reciprocate the wheel relative to the workpiece during grinding, in short longitudinal strokes parallel to the axis of the wheel, to produce a smoother surface on the workpiece. In many applications it may be desired, after said surface has been ground, to grind a shoulder surface on the workpiece with the side of the grinding wheel, which shoulder surface on the workpiece may, for example, be normal to the axis of the wheel.

Heretofore, in operations of this kind where a relative reciprocation between two members such as a grinding wheel and a workpiece is followed by a relative feeding movement between said members in a direction parallel to the reciprocating motion and beyond one of the limits of the reciprocation, it has been usual to effect reciprocation by movement of one of said members, such as the grindin wheel and to effect the subsequent feeding by movement of the other member, the workpiece. This has required actuation of two controls, one to stop the reciprocation of said one member and the other to effect feeding movement of the other member.

In the present invention a mechanism is provided which permits a quicker and more easily effected operation of this kind than has been heretofore possible. With the mechanism of the present invention the same member which has been reciprocated, for example, the grinding wheel, is also fed into the shoulder surface of the workpiece. With one movement of one control the longitudinal reciprocation of the grinding wheel is terminated and the grinding wheel is fed longitudinally into the shoulder surface beyond the limit of reciprocation.

In brief, in the preferred embodiment of the present invention, the grinding wheel spindle is operatively connected to a follower which is normally reciprocated by an oscillating driver. The driver comprises a roller eccentrically mounted on a drive shaft, the driver engaging one surface of the follower. The surface of the follower engaged by the driver is normally held in contact therewith by a spring and as long as such engagement is maintained, the grinding wheel is reciprocated between normal limits. A manually operable cam is positioned in registration with the follower and, when actuated, urges the follower, against the action of the spring, out of contact with the driver to terminate reciprocation of the grinding wheel. Further actuation of the cam urges the follower beyond the limits of normal reciprocation by the driver and thereby moves the grinding wheel in one direction beyond its normal limit of reciprocation. In this manner the side cutting surface of the grinding wheel is gradually fed into the shoulder surface of the workpiece for grinding thereof.

It is therefore an object of the present invention to provide an improved mechanism for successive reciprocating grinding and shoulder grinding.

It is another object of the present invention to provide a mechanism to terminate relative reciprocation of Patented Oct. 10., 1961 a grinding wheel relative to a workpiece and operable to effect movement of the grinding wheel in one direction beyond the limit of said reciprocation.

It is another object of the present invention to provide a mechanism operable with a single actuation to terminate automatic reciprocation of the grinding wheel on one surface of a workpiece and feed the grinding wheel into another surface thereof.

It is another object of the present invention to provide a simply constructed, effective, easily operated mechanism for both reciprocating plunge cut grinding and shoulder grinding.

Other objects and advantages of the present invention should be readily apparent by reference to the following specification, considered in conjunction with the accompanying drawings forming a part thereof, and it is to be understood that any modifications may be made in the exact structural details there shown and described, within the scope of the appended claim, without departing from or exceeding the spirit of the invention.

In the drawings:

FIG. 1 is a view of the wheelhead, partly in cross-section;

FIG. 2 is a view taken on the line 22 of FIG. 1;

FIG. 3 is a view taken on the line 33 of FIG. 1;

FIG. 4 is a view taken on the line 44 of FIG. 1; and

FIGS. 5a, 5b, and 5c are somewhat schematic views of the relative positions of the driver, follower, and manually actuated cam: when the follower is reciprocated between normal limits by the driver; when the follower is held at one of its normal limit positions by the cam to terminate reciprocation of the wheel; and when the follower is moved beyond said normal limit position by the cam to move the grinding wheel beyond its normal limits of reciprocation, respectively.

There is shown in FIGS. 1 and 2, the wheelhead 10 of a center type grinding machine which is mounted on the ways 11a and 11b of the bed 12 of the machine for movement towards and away from a workpiece 13 by mechanism which may be similar to that shown in US. Patent 2,641,876 of J. Decker and B. A. Kearns dated June 16, 1953, or any conventional mechanism. The workpiece 13 is mounted between centers 14 and 15 defining a workpiece supporting means which may, for example, be similar to the headstock and tailstock structures, respectively, shown in US. Patent 2,641,876 and mounted similarly thereto. The grinding wheel 18 has a peripheral cutting surface 18a and a side cutting surface 18b. The workpiece 13 shown in the present disclosure has cylindrical surface 16 which is ground by surface 18a of the wheel and a shoulder surface 17 which is ground by surface 18b of said wheel. While the headstock and the tailstock may be movably mounted to reciprocate a workpiece longitudinally relative to the grinding wheel 18 (to the right and left as viewed in FIG. 1) the present invention is particularly suited for plunge cut grinding where the workpiece is rotated in a fixed position and the wheel 18 is fed into the workpiece (toward the viewer of FIG. 1) and reciprocated longitudinally relative to the rotating stationary workpiece. With the mechanism of the present invention the longitudinal reciprocation of the grinding wheel can be terminated and the side cutting surface 18b thereof fed manually into the shoulder 17 for grinding.

The grinding wheel 18 is mounted on a spindle 19 in a conventional manner for rotation inside casing 20 connected to the wheelhead. The spacing inside the casing is suflicient to allow a limited longitudinal reciprocation of the wheel therein between the sides 20a and 20b thereof. The spindle is mounted in bearings 20 in the wheel-' head body 21 and extends through the body. A pulley 22 is mounted on the spindle outside the body oppo V I 3 site the grinding wheel for connection through drive belt 23 to a motor 24 mounted on the wheelhead. The spindle 19 passes through a recess 25 in the body and is positioned between the arms of a yoke26 therein .(see FIG. 3. The yoke is pivotally connected to the body 21 by pin 27.

The spindle 19 has a collar 28 integral therewith. A sleeve 29 encircles the spindle within the recess 25 and receives therein two rings 30 which. straddle the collar. Each'ring 30 is held against the collar by a second ring 31 which, in turn, is held in position by an externally threaded nut 32 in threaded engagement with the interior wall of the sleeve, the nut being held against rotation by a lug 33 screwed into the sleeve. The nuts 32 are secured tightly enough to minimize play between collar 28 and sleeve 29 but not so tight that rotation of the spindle 19, and collar 28 thereof, is prevented relative to the sleeve. Clearance is provided between the spindle 19, and the nuts 3-2 and rings 30, 31. V

The sleeve 29 is pivotally secured between the arms 'of the yoke 26 by pins 34 and 35 threadedly engaged with the arms of the yoke, the pins having shanks 36 and 37, respectively, received in the sleeve. The pin 34 also has a head 38. As the head 38 is moved a short distance parallel to the spindle 19 the yoke26 swingsthrough a small arc and the spindle is moved axially through the rotating connection formed between the collar 28 and sleeve 29. The sleeve is free to pivot on pins 34 and 35 and tends to remain aligned with the spindle 19, the clearance between the spindle and the parts received within the sleeve preventing contact between the rotating spindle and those parts asthe sleeve is swung by the yoke. Thus longitudinal reciprocation of the head 38 (left and right as viewed in FIG. 1) will reciprocate the spindle and hence the grinding wheel longitudinally relative to the workpiece.

The wheelhead body 21 has a sleeve 45 extending therethrough parallel to the spindle 19, the sleeve having an opening 46 in communication with the recess 25 through which the head 38 of pin 34 extends. On one side the head 38 is engaged by a pin 47 urged thereagainst by a spring 48 under compression, one end of which is received in the pin 47 and the opposite end of which is engaged with adjustable plug 49 in the body 21. On the opposite side the head 38 is engaged by an axially movable round shaft 50 having a fiat forming a slot 51 therein. A roller 52, eccentrically mounted on drive shaft '53, is received in the slot 51 in registration with the wall surfaces'thereoflincluding the surface 54 which is normal to the longitudinal axis A of the shaft and towards the head 38. The longitudinal span of the slot is greater than the limits of travel of the periphery of the eccentrically mounted roller 52 so that the follower may be moved beyond the reach of the roller even.

though the roller remains in the slot. In the absence of other forces on the shaft 50 the surface 54 will be yieldlingly urged against the eccentric roller 52 by the spring urged pin 47 acting through the movable head 38. The roller 52, when drive shaft 53 is rotated, will define an oscillating driver, and the shaft 50 will constitute a follower to which reciprocating motion is imparted by the a driver, The reciprocating motion will be transmitted to thehead 38 of pin 34 since it is urged into contact with the follower by the spring urged pin 47 and hence this motion will be transmitted to the grinding wheel 18.

The drive shaft 53 is snuglyreceived in a' sleeve 55 which is rotatably mounted in bearings 56 and 57, hearing 56 being mounted in body 21 and bearing 57 being mounted in an insert 58 secured in the body 21 by screws (not shown). A ring 59 keyed to sleeve 55 is received over bearing 57, and nut 69 is threadedly engaged with sleeve 55 over ring 59. A knob 61 and skirt 62 are received on the shaft 53 over nut 60. A secon d sleeve 63 is received over sleeve 55 between the bearings 56 and 57 and is keyed to sleeve 55 at 64 so that rotation of gear 65 integral therewith which is engaged with worm 6 6 on shaft 67 (see FIG. 2). This latter shaft is supported in body 21 by bearings 68 and extends outside that body where it receives a pulley 69 which is connected by belt 70 to pulley 22 for driving by motor 24; An adjustable idler pulley 71 is provided for adjustment by knob 71a of the tension in the belt 70. It will therefore be evident that the shaft 53 will be continuously driven and roller 52 will define an oscillating driver capable of reciprocating follower 50 between predetermined positions established by the eccentricityof the roller 52 when the surface 54 is urged against the driver. Thus the grinding wheel, when surface 54 is urged against roller 52, will be reciprocated between predetermined limits.

There is provided a simple manual control effective to terminate reciprocation of the grinding wheel and move the grinding wheel beyond one of its predetermined limits to grind the shoulders 17. A shaft 75 rotatably mounted in body 21 has connected at one end a cam 76 positioned adjacent the end 77 of follower 50 opposite the end which engages head 38 of pin 34. Shaft 75 has a lever 78 connected thereto outside the housing to actuate the cam (see FIG. 4). The lever 78 is held in the center, or intermediate, position shown in FIG. 4 when the arms 81 and .82 are both lowered as shown, the. arms being pivotally mounted by pin 85 .betweenupstanding ears 86 connected to body 21, for swinging in a vertical plane. When the arms are raised the lever is rotatable in either direction to predetermined limits defined by contact of the shoulder 83 of the lever with the pin 84 carried in body 21.

As shown best in FIG. 2, the cam 76 has a that surface 79 and a curved surface of varyingradius; When the lever, as viewed in FIG. 4, is in the extreme counterclockwise position, the flat surface 79 of the cam, which constitutes the low portion thereof, is in registration with, and spaced from, the end 77 of the follower, permitting reciprocation of the follower between normal predetermined positions, as shown in FIG. 5a, in response to the rotation of the driver 52. When the lever 78 is rotated clockwise to the intermediate position as shown in FIG. 4, the point 80a of surface 80, which constitutes an intermediate portion thereof, is swung into contact with the end 7'7 of the follower 50 and the follower is urged to the left, as viewed in FIG. 1, against the spring 48, to the predetermined position where the follower is held at the limit of travel of the eccentric roller 52, as shown in FIG. 5b, so that reciprocation of the follower by the eccentric roller is terminated. .As the lever 78 is swung towards its extreme clockwise position, as viewed in FIG. 4, the point 80b which constitutes thehigh portion of the cam surface is swung into contact with'end 77 of the follower, urging the follower beyond thepredetermined position to which it is driven by the driver, as shown in FIG. 50, and thereby feeding the grinding Wheel beyond its limit of reciprocation and into the shoulder surface 17.

In operation a workpiece 13 is placed between centers 14 and 15 and infeed of the grinding wheel 18 toward the workpiece is begun. The lever 78 is placed in its extreme counterclockwise position and the grinding wheel is automatically reciprocated as it is fed into surface 16 of the workpiece. When the grinding of surface 16 is completed, the lever 78 is swung through the intermediate position, at which time reciprocation of the grinding wheel stops, toward the extreme clockwise position. This feeds the grinding wheel 18 longitudinally relative to the workpiece to bring the side cutting surface 18b into grinding contact with shoulder surface 17. The centers 14 and 15 may be located so that surface 17 is ground to size when the lever 78 reaches its clockwise limit, or, if the centers are not so set, longitudinal feeding may be terminated when gage 87 operatively connected to plunger 47, and hence to the grinding Wheel 18, indicates the shoulder is sleeve 63 will rotate shaft 53. The sleeve 63 has a worm 75 ground to desired size.

For operations involving no shoulder grinding where selective reciprocation is desired, arm 82 may be lowered and lever 78 actuated between its intermediate position and its extreme counterclockwise position, as viewed in FIG. 4. For operations where reciprocation is not required and selective shoulder grinding is desired, arm 81 may be lowered and lever 78 actuated between the intermediate position and the extreme clockwise position as viewed in FIG. 4. If neither reciprocation nor shoulder grinding is required, both arms 81 and 82 may be lowered and lever 78 locked in the intermediate position as shown in FIG. 4.

What is claimed is:

In a grinding machine having a grinding wheel and a follower operatively connected to the grinding wheel, said follower normally urged in one direction against an oscillating driver for reciprocation between normal limits, the combination of a cam adjacent the follower having a manually operated lever connected thereto, said cam spaced from the follower when the lever is in one extreme position, said cam engaging the follower to move the follower oppositely to said one direction to disengage the follower from the oscillating driver when the lever is moved to an intermediate position, said cam moving the follower further in said opposite direction to feed the grinding wheel beyond one of said normal limits as the lever is moved to an opposite extreme position, a stop member selectively swingable into the path of the lever to engage the lever at the intermediate position and prevent movement of the lever in one direction from said intermediate position, and a second stop member selectively swingable into the path of the lever to engage the lever at the intermediate position and prevent movement of the lever in the other direction from said intermediate position.

References Cited in the file of this patent UNITED STATES PATENTS 

